Why Do We Measure Blood Pressure on the Left Arm?
It’s never been easier to take your own blood pressure at home. Automated digital blood pressure monitors measure heart rate and take a blood pressure reading, which consists of a systolic number (measurement of the pressure against your artery walls when your heart beats) and a diastolic number (measurement of the pressure between beats). Doctors consider a systolic/diastolic measurement of 120/80 to be normal. An accurate reading requires that you to make a few preparations and use the blood pressure monitor properly. Let’s take a look at how to take your own blood pressure accurately.
Determining Which Arm to Use
Traditionally, healthcare providers have taken blood pressure readings on the left arm. That’s because the heart sits slightly to the left of the midline in your chest. The body’s largest blood vessel, the aorta, exits the left side of the heart and transports blood through blood vessels throughout the body. The coronary arteries coming directly off of the aorta into the left arm are more likely to become stiffer and obstructed than those going into the right arm. Some doctors and nurses will take blood pressure readings in both arms because the readings will vary. A large discrepancy between two arms can be a warning sign of arterial stiffening.
Taking Your Blood Pressure
Follow your healthcare provider’s instructions on when and how often to take your blood pressure, and try measuring your blood pressure at about the same time each day. Whether you have a manual or a digital blood pressure monitor, follow the instruction booklet carefully. Here are the five basic steps for taking a blood pressure measurement using an automatic digital monitor:
1. Get ready. Before taking a reading, be sure to avoid factors that can cause blood pressure to rise temporarily. These factors include stress, cold temperatures, exercise, caffeine, coffee, some medications, and a full stomach or bladder.
2. Get set. Rest in a chair next to a table for 5 to 10 minutes before taking the measurement. Sit up straight with your back against the back of the chair and with your legs uncrossed and on the ground. Rest your forearm on the table with the palm of your hand facing up. Your elbow should be positioned at heart level.
3. Position the cuff. Tighten the cuff on your bare upper arm one inch above the bend of your elbow. Take the measurement on your left arm unless directed by your healthcare provider to take the reading on your right arm. The cuff should be tight enough so that you can slip only two fingertips under its top edge. Settle yourself by waiting briefly before proceeding to the next step.
4. Start the machine. Press the Start button and remain still and quiet as the machine takes the measurement. The cuff will inflate (and tighten) and then slowly deflate. When the reading is completed, the monitor will display your blood pressure and heart rate. If the monitor doesn’t show a reading, reposition the cuff and restart the machine.
5. Record the results. Be sure to write down your systolic and diastolic numbers, heart rate, and which arm you took the reading on.
6. Take a second reading. After a few minutes, repeat the steps above to take another reading and record the results.
Keeping Track of Your Blood Pressure
Monitoring your blood pressure is extremely important. High blood pressure is a major cause of heart disease, heart attacks, strokes, and other health conditions. One easy way to keep track of your blood pressure is to use the Semler Heart Club app. This all-in-one, cardiologist-designed app helps you track your daily steps and blood pressure and gives you access to important medical data. Learn more about how Heart Club can help improve your general heart health.